Artificial insemination attempts to treat infertile couples by solving their infertile problems. One of the main causes of infertility is that small numbers or none of the ejaculated spermatozoa reach the egg in the ampullary portion of the tube. Oligozoospermia (small sperm number in the ejaculate), asthenozoospermia (decreased sperm motility), low semen volume, and hostile cervical mucus are the common reasons for this occurrence. These factors are clinically diagnosed by persistently negative or poor postcoital tests, i.e., absence of sperms or motile sperms in the secretion of the uterine cervix after natural sexual intercourse.
Intrauterine insemination (IUI) with husband's semen is widely used in the treatment of infertile couples with cervical mucus hostility and moderately deranged male semenograms. The intrauterine insemination consists of a bolus, one-off injection into the uterine cavity of a large number of motile, washed and concentrated sperms condensed in a small volume of 0.2 to 0.4 ml. of culture media. This is the classical (conventional) bolus intrauterine insemination technique. An important disadvantage of the classical IUI bolus technique is the deposition of very large number of sperms into the uterine cavity. This may have an adverse immunological impact, and may cause polyzoospermia. Spermatozoa placed in the uterine cavity migrates quickly to the fallopian tubes and uterine cavity. Hence, the period time of fertilisation is limited and IUI has to be perfectly coordinated with ovulation for fertilization to take place. As a result of these disadvantages, the conception rate for classical IUI is very low.
To perform classical IUI an insemination catheter is used to introduce the semen into the uterine cavity through the cervix. This catheter is removed immediately after the introduction of the sperms into the uterine cavity.